Can't get any sleep

Lately i just can't seem to get myself to have good sleep...And it's starting to get me. I really need the whole night for my sleepings...cause i have very long days of school and travelling. I've tried so many things,...warm milk with a cube of anise. Liquid lavender to put on your body and i also let a few drips fall on my pillows...but it doesn't seem to work. I'm starting to hate it. So if you have any good advice...please drop it in a comment i would be so happy! And who knows maybe your advice will work?